Kimmo Timonen wanted to be absolutely sure before he committed to one more NHL season. After the Philadelphia Flyers' campaign ended, he took a couple weeks off and started training again. Running felt fine. So did riding a bike.

Two months after signing a one-year extension with the Flyers, Timonen's health – let alone hockey future – is a big question mark. The 39-year-old Finn has blood clots in his right leg and both lungs, according to general manager Ron Hextall.

"Kimmo is currently being treated for this disorder back in his home country of Finland," Hextall said in a statement. "His return to play is yet to be determined."

The doctor told Timonen to go to the hospital, where he expected to be released Wednesday.

"I haven't talked to him yet," Hextall said. "I reached out to him twice. He's in the hospital and he did send me a text. He seemed very frustrated, but we're all happy for Kimmo, (wife) Johanna and his three children that he's doing fine."

Hextall doesn't expect Timonen, who signed a one-year extension in mid-June, to be in training camp, so he signed 24-year-old free agent Michael Del Zotto to a one-year pact reportedly worth $1.3 million. Del Zotto didn't receive a qualifying offer from the Nashville Predators this summer.

As for Timonen, Flyers doctors have been in contact with doctors in Finland, where they say Timonen is in "stable" condition. In 2-3 weeks, when the five-time Olympian is able to travel again, he'll return to South Jersey where Flyers doctors will pick up evaluation.

"This could be a long-term thing and we have to prepare as an organization as if it is a long-term thing," Hextall said. "Can he play at some point next season? I don't have the answer to that.

"First and foremost, we're worried about Kimmo Timonen the person, not Kimmo Timonen the hockey player."

Timonen went back to his native Finland in mid-June after he signed the deal that could be worth up to $3.5 million if he meets performance bonuses.

The defenseman had six goals and 29 assists in 77 games for the Flyers last season, while averaging 20:20 of ice time, his lowest average since his rookie campaign. Back in the 2008 playoffs, Timonen had a blood clot in his left ankle after blocking a shot by Montreal defenseman Andrei Markov.

Last season, Pittsburgh Penguins goalie Tomas Vokoun, 38, missed all 82 games when it was revealed that he had a blood clot in his pelvis. Winnipeg Jets defenseman Paul Postma, 25, missed a big chunk of last season when he discovered a blood clot in his leg, too.